Your Opinion

[cody@schouten.us]

So I'm looking at several bids for a roof mounted PV system. I've narrowed it down to a couple of companies. I was hoping to get people's opinion. They're all bidding on a about 10kw system.

Bid 1:
Panel: 37 Amerisolar 270w ( AS-6P30)
Inverter: SMA 5.0US
Price Per Watt: $2.30
Company Start Year: 2003

Bid 2:
Panel: 35 Canadian Solar 285w ( CS6K-285M)
Inverter: SMA 5.0US
Price Per Watt: $2.40
Company Start Year: 2015

Bid 3:
Panel: 33 QCell 300w ( Q.PEAK-G4.1)
Inverter: SMA 5.0US
Price Per Watt: $2.42
Company Start Year: 2013

These are going to be installed on my home near Orlando FL.

[max2k]

So I'm looking at several bids for a roof mounted PV system. I've narrowed it down to a couple of companies. I was hoping to get people's opinion. They're all bidding on a about 10kw system.

Bid 1:
Panel: 37 Amerisolar 270w ( AS-6P30)
Inverter: SMA 5.0US
Price Per Watt: $2.30
Company Start Year: 2003

Bid 2:
Panel: 35 Canadian Solar 285w ( CS6K-285M)
Inverter: SMA 5.0US
Price Per Watt: $2.40
Company Start Year: 2015

Bid 3:
Panel: 33 QCell 300w ( Q.PEAK-G4.1)
Inverter: SMA 5.0US
Price Per Watt: $2.42
Company Start Year: 2013

These are going to be installed on my home near Orlando FL.

have you done your load analysis: how much you consume and how much out of that can be optimized? Reducing required system size is one of the most efficient ways to save money on solar. 10kW is kind of high for residential setting but everybody's situation is different and may be you need that much.

[cody@schouten.us]

I have reduced it quite a bit. It has good insulation, all appliances are no older than 2 years. The A/C is set as high as the wife will allow . I'm considering a hybrid water heater to maybe trim off a few more kw's, I'm not interested in doing solar water at this time.

[littleharbor]

Do you have gas available? How do you cook, heat dry clothes?

[cody@schouten.us]

It's all electric. Even the water comes from a well and pump.

[Mike7381]

A 10kw system with 5kw inverter? Are they using 2 or just one?

[ButchDeal]

A 10kw system with 5kw inverter? Are they using 2 or just one?

Why are all the bids SMA? Why such small inverters ?
Are there shadows? Multiple azimuths ?

[cody@schouten.us]

We originally got other bids for enphase and SolarEdge but we liked the plug that the SMA inverter offers. Some of the bids are for multiple inverters, some are for a single bigger one I wrote them wrong in the original post.

All panels have no shade and are facing the same direction South.

[max2k]

We originally got other bids for enphase and SolarEdge but we liked the plug that the SMA inverter offers. Some of the bids are for multiple inverters, some are for a single bigger one I wrote them wrong in the original post.

All panels have no shade and are facing the same direction South.

SMA inverter 'plug' comes with strings attached (pardon the pun) - it only works when grid voltage is not present and it also disappears as soon as there's cloud in the sky. It is also limited in power it can supply to the 1/3 - 1/5 of the inverter rated AC output. If you use 2 inverters you'd get 2 plugs instead of 1 with combined power output. IMO it has more marketing value than practical. It would be much more practical if they could feed house loads through the same AC output in case grid is out but that's not the case probably due to some regulations allowing it to have 'grid interactive' designation.

[littleharbor]

SMA inverter 'plug' comes with strings attached (pardon the pun) - it only works when grid voltage is not present and it also disappears as soon as there's cloud in the sky. It is also limited in power it can supply to the 1/3 - 1/5 of the inverter rated AC output. If you use 2 inverters you'd get 2 plugs instead of 1 with combined power output. IMO it has more marketing value than practical. It would be much more practical if they could feed house loads through the same AC output in case grid is out but that's not the case probably due to some regulations allowing it to have 'grid interactive' designation.

The secure power feature needs to be manually switched on in the event of grid failure and as mentioned is limited to 2000 watts or whatever is available from the array, whichever is less. Another catch is it must be switched OFF. Don't know if there is some indicator alerting you that the grid is back up. Sounds like you need some other means of knowing the grid is back.

[cody@schouten.us]

SMA inverter 'plug' comes with strings attached (pardon the pun) - it only works when grid voltage is not present and it also disappears as soon as there's cloud in the sky. It is also limited in power it can supply to the 1/3 - 1/5 of the inverter rated AC output. If you use 2 inverters you'd get 2 plugs instead of 1 with combined power output. IMO it has more marketing value than practical. It would be much more practical if they could feed house loads through the same AC output in case grid is out but that's not the case probably due to some regulations allowing it to have 'grid interactive' designation.

We're aware of these considerations. We live in a hurricane prone area. These plugs would be enough to keep my fridge running during the day so my food doesn't go bad.

[SunEagle]

We're aware of these considerations. We live in a hurricane prone area. These plugs would be enough to keep my fridge running during the day so my food doesn't go bad.

Just be aware that even a little bit of clouds will greatly reduce or completely stop the output of those SMA secure power sources which is something a refrigerator does not like to see. Multiple starts and stops can hurt it if the compressor is in the middle of running.

[cody@schouten.us]

Just be aware that even a little bit of clouds will greatly reduce or completely stop the output of those SMA secure power sources which is something a refrigerator does not like to see. Multiple starts and stops can hurt it if the compressor is in the middle of running.

So should I be pushing for a different inverter than the SMA with the plug? I'm not planning on this working like a generator, just a nice bonus to a good quality inverter.

[sensij]

So should I be pushing for a different inverter than the SMA with the plug? I'm not planning on this working like a generator, just a nice bonus to a good quality inverter.

That is the only inverter that offers any access to your PV system, without going to a hybrid and adding the expense and maintenance of batteries.

If you'd like to operate something like a fridge that won't tolerate starts and stops well, and may have a startup surge in excess of what the SPS can deliver, you could add an appropriately sized UPS to ride through fluctuations from clouds.

I agree with max2k that it is more gimmick than anything, but all else being equal, I would rather have an inverter with that capability than without.

To get the most out of it, instead of splitting the array between two 5 kW inverters, you might want to use a 6 kW or 7.6 kW and a 3.8 kW or 3 kW.

[ButchDeal]

That is the only inverter that offers any access to your PV system, without going to a hybrid and adding the expense and maintenance of batteries.

If you'd like to operate something like a fridge that won't tolerate starts and stops well, and may have a startup surge in excess of what the SPS can deliver, you could add an appropriately sized UPS to ride through fluctuations from clouds.

I agree with max2k that it is more gimmick than anything, but all else being equal, I would rather have an inverter with that capability than without.

Another option though similar is to go with SolarEdge SE7600. This will not give you power BUT you can upgrade the SE7600 to the Storedge in the future and add an LGChem RESU10H for a full bimodal inverter system which would have more capabilities than the SMA marketing toy.

You could also install the StorEdge now. it would cost more than the SE7600 but will work fine without the battery and you could add the battery latter.